Absorption and retention of magnesium and some trace elements by man from typical Indian diets

The bioavailability of magnesium and 4 other trace elements from isocaloric Indian diets was determined in 6 healthy young men of low socioeconomic status. Average diets of very low and low income groups from 4 regions of India, as well as a fish, mutton, and pulse diet were each fed for 11 days. Trace element contents of cooked diet samples, water, urine, and feces were analyzed by atomic absorption spectrometry. Absorption of trace elements from the diets was 60%, 18%, 34%, 14%, and 16% of dietary intake for chromium, copper, magnesium, manganese, and zinc respectively. The quality of diet had little effect on chromium absorption. Copper absorption from diets containing meat, fish or large amounts of the legume was high. Most of the Indian diets did not provide sufficient zinc to meet daily requirements. Subjects on 1 regional diet with high fiber content were in negative magnesium balance. Daily dietary intakes of 51.5 micrograms chromium, 1.73 mg copper, and 4.15 mg manganese were needed to keep subjects in balance. (nm)